Question: What are you doing to screen for systemic diseases, specifically diabetes?
Very few dental offices have printed health history forms that ask appropriate questions about risk factors for diabetes mellitus (DM). We often ask, "Do you have a history of diabetes?" and end the conversation at the first "no." Rarely do the questions go beyond that basic level.
There are several questions the dental team should ask. First, does the patient have a family history of DM? Patients will not volunteer this information. If a first-degree relative (mother, father, sister, brother) has DM, the patient has an increased risk of having it. This is particularly true for type 2 DM, the most common type, which has a stronger inheritance pattern than type 1 DM. Second, women should be asked about a history of gestational DM with any past pregnancies. Gestational DM is a major risk factor for type 2 DM; between 35% to 60% of women who have had gestational DM will end up with type 2 DM within 10 years postpartum.
Next, what is the patient’s racial group? Latinos and African-Americans have a higher risk of type 2 DM than do Asians or Caucasians. Is the patient overweight or obese? Obesity is a major risk factor for type 2 DM. The patient’s blood pressure should be evaluated, and he or she should be questioned about cholesterol levels, as both hypertension and hypercholesterolemia are closely associated with type 2 DM.
This simple medical history is the best key to determining which patients require further evaluation for DM. Just because a patient is an obese African-American with hypertension and has a past history of gestational DM does not mean that she has DM. But it does mean that she has an increased risk for the disease and may be a candidate for further evaluation.
If a patient is at increased risk for undiagnosed DM, then appropriate laboratory testing is indicated and may include a fasting plasma glucose (FPG), a casual plasma glucose (CPG), or a glycated hemoglobin (HbA1c) test. Diagnosis can only be made through laboratory testing, not through point-of-care (POC) tests such as a glucometer or POC glycated hemoglobin tests. A glucometer can be used to test the current glucose level in capillary blood, but the dentist must exercise caution in using a glucometer for routine screening of patients for diabetes. The American Diabetes Association does not recommend glucometer testing as a routine screening tool in a non-healthcare environment. But a dental office may be an appropriate healthcare setting for glucometer testing in patients with known risk factors for DM.
If the dentist decides to do such glucometer testing, he or she must be able to interpret the results of those tests. What is a normal fasting glucose level? A normal FPG is < 100 mg/dl; an FPG over 126 mg/dl suggests diabetes; an FPG between 100 mg/dl to 125 mg/dl indicates impaired fasting glucose. If the patient did not fast for 8 hours, what is a normal (casual) glucose level? A CPG over 200 mg/dl suggests diabetes.
Importantly, if a dentist is going to consider doing in-office glucose screening, he or she must know what to do with the results. For example, if a patient has a random, casual glucometer test and the reading is 320 mg/dl, that is clearly above the threshold for DM and appropriate physician referral is needed. But what if the reading is close to or within the normal range? Does that glucometer reading mean the patient does not have DM? It does not. Sometimes undiagnosed DM patients will have glucometer readings close to or within the normal range. Likewise, a non-DM patient who has just eaten a large, carbohydrate-rich meal may have high glucometer readings despite the fact that they do not have DM.
Finally, use of an in-office glucometer or POC glycated hemoglobin test requires compliance with Clinical Laboratory Improvement Amendments (CLIA), which govern medical laboratories. Under federal law, a dental office that does glucometer testing or HbA1c testing is considered a medical laboratory and must comply with CLIA. Compliance is relatively easy for simple glucometer testing and involves an application and bi-annual recertification and fee payment.
I take an extensive medical history and perform an exacting extraoral and intraoral examination. This approach yields the maximum amount of information in a very cost- and time-effective manner. One of the most informative parts of the medical history is the patient’s drug history. If the patient takes glucophage, it is for type 2 DM. If the patient takes levothyroxine, it is for hypothyroidism. If you know what medications your patient is taking, you often know what they are taking it for. Certainly, there are patients who do not see a physician. The medical history will provide this information, as well if you ask, "When was your last medical examination?"
The cardiovascular literature clearly states that past the age of 55, if you live to your life expectancy, you have a 90% chance of developing hypertension. In this case, age alone is a risk factor. When a patient tells you they are taking a diuretic and a calcium channel blocker, they are being treated for hypertension. Moreover, blood pressure measurement has become the standard of care. At our dental college, blood pressure is taken before every appointment. This way, we can monitor the patient for the stability of their blood pressure and compliance with their physician’s advice, to ensure that our dental care can be delivered in a safe manner. While we are at it, we take their pulse for not only the rate, but also to determine if the rhythm is regular or irregular.
There is a significant amount of clinical and research interest in the association between diabetes and the periodontal diseases. No one will argue that a nidus of infection anywhere in the body (including the oral cavity) will deleteriously alter the patient’s glycemic control. Type 2 DM is genetically acquired. Is there a family history of DM? Is the patient taking medications to control DM? Are they overweight or prone to infection? Do they have significant periodontal disease that seems severe relative to the local factors present? We do not routinely use a glucometer in our clinics, although they are often advocated for use in dental practices, but there should be an indication to perform the test in a patient. Any test should be used for a disease in the patient’s differential diagnosis. In the patient who has not recently seen a physician, who has a positive family history for diabetes, is overweight, and has rampant periodontal disease in spite of good oral hygiene practices, a screening blood glucose level 2 hours after eating is certainly indicated.
What concerns me is that we appear to be more concerned with primarily medical diagnoses such as diabetes and hypertension than we are with oral cancer. There will be approximately 45,000 new cases of oral cancer diagnosed in the United States this year and one person will die of this disease each hour. If detected early, the survival rate approximates 90%. Conversely, if found late, the survival rate drops to less than 20%. If oral cancer metastasizes, it becomes a systemic disease. So, maybe, the best answer to the posed question regarding dentists screening for systemic disease is for them to prevent an oral disease from becoming a systemic one.
As dentists we have a wonderful opportunity to enhance our patients’ health by screening for systemic diseases. The frequency with which we see our patients, the length of time we spend with them, and the oral evaluation we do at each and every appointment gives us that unique opportunity.
While many physicians refuse to recognize or act on the evidence, it is very clear that in addition to systemic disease impacting oral health, oral health impacts systemic disease, making a partnership between dentists and physicians critical for overall health. Having had the opportunity to treat many physicians, I have crossed the line on numerous occasions when, after looking at a photograph of a mouth with advanced periodontal disease in a diabetic, I have allowed my physician colleagues/patients to explain to me why addressing this infection is somehow different than addressing an infection in a foot or a leg. The concept that dentistry is a separate and independent discipline as opposed to a branch of medicine has been shattered.
With this evolution in thinking comes greater responsibility. The opportunity to screen our patients for hypertension, diabetes, and other systemic diseases on a regular basis is a wonderful service to provide but also demands that we continuously update our knowledge base, skill set, and communication skills. As dentists, we are afforded the luxury of spending significant time with our patients and, therefore, an in-depth medical and dental history can be obtained. Of all the screening techniques, from glucose monitors to chairside A1c, the review of the medical history is the most important. Asking if a patient is diabetic is not enough; the medical history form is necessary but not sufficient. The real information is gleaned and the real service is provided by jumping off those "yes" or "no" questions and drilling deeper into our patients’ family, personal, and medical histories. These conversations allow us to better treat our patients and truly participate in their healthcare.
About the Authors
Brian L. Mealey, DDS, MS | Dr. Mealey is the graduate program director in the Department of Periodontics at The University of Texas Health Science Center at San Antonio, San Antonio, Texas.
Michael A. Siegel, DDS, MS, FDS RCSEd | Dr. Siegel is a professor and chair of the Department of Diagnostic Sciences in the College of Dental Medicine, and a professor of dermatology in the College of Osteopathic Medicine at Nova Southeastern University, Fort Lauderdale, Florida.
Jeffrey Kopman, DDS, MMSc | Dr. Kopman is the clinical director of the New York Institute for Advanced Dental Studies, New York, New York.